Mk4 Golf 1.6 16v Throttle Body Cleaning

[James White]

Hello, I've just recently joined as I bought a Mk4 Golf last weekend and I am new to the forum.

Been doing a little research on a problem I had which was the EMISSIONS WORKSHOP indicator on the dash. Many threads I read mentioned cleaning the throttle body and realigning it.

I am new to the diagnostic software but have downloaded VCDS-Lite and bought a cheap ebay cable. Cleared the fault code that was causing the EMISSIONS WORKSHOP light but obviously didn't cure the problem so I am just waiting for it to come back on.

Back to the throttle body. My question is: what is the safest method to clean it?
Can you clean it while it is attached (which I have done on previous vehicles) or should I remove it? Can I use carburetor cleaner instead of throttle cleaner (as I already have carb cleaner available). And can I spray into the intake with either the engine running or not and someone feathering the throttle?

Also, I haven't tried it yet but can you realign the throttle body with VCDS-Lite (free version)?

Many thanks
James

[Rob69]

James
You didnt mention what code it had logged, but check its not egr related before going into throttle body cleaning.

[James White]

James
You didnt mention what code it had logged, but check its not egr related before going into throttle body cleaning.

Good point here is a snap shot of the VCDS code


I also had the car stall a couple of times whilst slowing down for roundabouts or junctions and also whilst accelerating away on a dual carriageway, lost power and the engine cut out.

Thanks
James

[Rob69]

james
check for vacuum leaks as engine is running lean. Also check maf sensor, you should be able to do this with vcds lite. More info on this forum or online. Sorry got to go, at work today so need to look busy.

[James White]

Will check for vacuum leaks, thanks for the suggestion.

Still looking for any recommendations on cleaning the throttle body, "Can you clean it while it is attached (which I have done on previous vehicles) or should I remove it? Can I use carburetor cleaner instead of throttle cleaner (as I already have carb cleaner available). And can I spray into the intake with either the engine running or not and someone feathering the throttle?"

Thanks
James

[zmotor]

if your cleaning it while its attached please please do not have the engine started...the chemicals will ignite etc etc....big no no

carb cleaner has a little lube in it if i remember correctly any cleaner will do really, best to take it off but im not sure if there is a gasket or if it will come off in one piece...spray a clean rag and reach in and clean it out would be my suggestion. If you spray directly into the throttle body and clean it...jam the throttle open and let it air out before closing it and starting the car

[James White]

Thanks zmotor. My only concern is manually moving the butterfly valve. Because I'm not used to this electric set-up (previously owned older cars) can you move it with, say you finger, without damaging anything? It's not a drive by cable set-up, on previous cars I've owned I've just turned the part that holds the cable to the throttle to clean inside.

I would prefer to take it off and clean it properly. Gaskets are relatively cheap anyway. The engine doesn't haunt, but does travel between 25-50rpm occasionally, mostly when I'm holding the rev's at 12,00-1,500.

[Rob69]

you cant realign throttle body with shareware vcds. Do all the basic checks before the throttle body. Check out other posts here for more info.

[Doctle Odd]

Don't attempt to move the butterfly valve it's connected to little plastic gears. The throttle body is best removed for cleaning the underside. Is it very dirty? You'll need access to the full version of VCDS or similar to align the throttle

[James White]

Thanks for all your replies, guys. Answered all the questions I had. Will let you know how I get on in the New Year.

Thanks
James